The central theme of An Insular Possession is captured in the description of the southern China trading route, the Macao Roads, which begins the novel. Lifeline of the region, “the river succours and impedes native and foreigner alike; it limits and it enables, it isolates and it joins.” The paradoxes of the river reflect its unpredictability: Passages once unobstructed are, suddenly, impeded by boulders and sand bars; into the firm margin of the mainland, peninsulas are carved overnight and later break away to form islands; the navigable, single river becomes many rivers, unchartered. Like its waterway, Canton, too, passes swiftly through stages of transition: Once a home to Muslims, it was invaded by the current natives, only subsequently to be seized by the British and again reprised by the Chinese. Both trading route and trading town suggest that reality itself, far from a fixed, objective fact, is a mutable entity, a panorama in constant flux.

The novelist and his characters strive, therefore, to determine the most reliable, accurate means of interpreting their fickle world. Following a successfully vanquished insurrection in Canton, for example, the town’s natives surprise their captors by rising again, abducting hostages trapped in the trading houses. The conservative Canton Monitor interprets the attack as a clear sign that the Chinese are unruly, immoral, and willful, and must be taught, through utter destruction, obedience to the queen. In response, Eastman argues that the attack was instigated by Indian sepoys, a clever British ploy to provide justification for slaughtering the Chinese. Both interpretations, however paradoxically, are true, for each is a matter of perspective. Yet the editors accuse each other of blind falsehood, because their faith in their own perceptions denies the possibility of alternatives.

Mo raises the theme to a conscious level in his characters through Harry O’Rourke. As one of the original Impressionists, O’Rourke marks the transition in art from strict attention to realistic detail to subjective interpretations of the world. His art concentrates not on portraying the world but rather on the impressions the world makes on him. Rejecting this innovation, Eastman challenges O’Rourke with the newly invented daguerreotype, which he believes, in providing factual representations of the world, will replace the pictorial arts. Yet upon operating the newfangled machine, Eastman must admit that it fails to record the world objectively. The variables of light exposure and framing render the photographer as much an interpreter as the painter, and Eastman finally accepts O’Rourke’s theory that life, after all, will imitate art. When he finds himself dueling with the Canton Monitor’s editor, as he had so recently dueled with an actor in The Rivals, Eastman requires no more convincing on the subject.

The outcome of these investigations into the nature of reality is consistently paradoxical. Reality is absolute, Mo suggests, but it is not universal: For any individual, there is a single reality, but for the next individual that reality may well differ. Ultimately, this theme serves the novel’s purpose by explaining Great Britain’s chief failure in building her empire. Rather than peacefully coexisting in this foreign world, Great Britain hopes to dictate reality for all of its people, bringing her government and galas and drawingroom chatter, imposing her values with the force of an ironsided steamer.